1. The Field of the Invention
The present invention relates to electrical junction boxes as used for the connection of conductors and the mounting of electrical receptacles and fixtures. In particular, the present invention relates to electrical boxes used in conjunction with construction panels such as structural insulated panels (SIP""s) which have an exterior layer of plywood or similar material and an interior layer of foam and insulated concrete panels (ICP""s) which have outer layers of rigid insulation and an inner layer of concrete. The electrical junction boxes of the present invention are particularly suited for mounting in a round hole drilled in the surface layer of such panels.
2. The Relevant Technology
Electrical junction boxes are commonly used in the construction industry for the connection and termination of electrical conductors and for the mounting of electrical receptacles, fixtures, and other apparatus. They are used in both residential and commercial buildings though their features may vary for different applications. In a typical installation, electrical boxes are placed in the wall, floor or ceiling of a structure by fixing them to the structural members. In a wood-frame residential building, electrical boxes are generally equipped with flanges or holes for receiving nails or screws with which they are fixed to framing members. These boxes are typically nailed or screwed to a wall stud, floor joist, ceiling joist or rafter in a position that will allow access to the box through the finished surface of the wall, ceiling or floor.
Once the typical electrical box is attached to the framing member, a surface finish material is attached to the framing to provide a finish surface to the building or room. For walls, common finish materials include drywall or sheetrock, stucco, masonry units, and wood, aluminum or vinyl siding. Electrical boxes are typically mounted in a manner that aligns one side of the box with the outer finished surface of the wall, floor or ceiling. The electrical box generally protrudes through the wall covering material so as to be flush with the outer finished surface of the wall. Mounting in this manner allows access to the box once the finished surface is complete and allows for mounting of electrical receptacles and fixtures directly to the box.
Structural insulated panels (SIP""s) typically comprise two exterior layers separated by an interior layer of foam insulation. The exterior layers are generally composed of plywood, oriented-strand board or a similar material. The interior layer is generally composed of a substantially rigid insulation material such as expanded polystyrene or polyurethane.
In many SIP""s electrical wiring is routed through electrical chases that are formed in the interior foam layer. Chases may be molded, drilled, routed or otherwise formed in the foam layer. In order to utilize these chases, an electrical box must be mounted in the SIP at a location that will intersect a chase. Currently, this mounting is performed by drilling a small hole in the exterior layer of the SIP sufficiently large to accept the blade of a saw. A saw is then used to cut a hole in the exterior layer of the SIP, the hole being shaped to conform to the shape of the electrical box. The box is then mounted in the hole and fastened to the exterior layer of the SIP with screws. When mounting, the installer must mount the box in a position that allows the box to protrude outwardly from the surface of the SIP to allow for the thickness of the wall covering material that will be applied to the wall. This process involves many steps and tools and generally results in a poorly secured and inaccurately placed box.
Insulated concrete panels (ICP""s) are another type of construction panel. ICP""s have an inner layer or core composed of concrete and exterior layers on either side of the concrete core which are composed of rigid insulation. ICP""s may be pre-cast with their exterior insulation layers so that they may be used in a tilt-up style construction or they may be fabricated on-site using forms composed of rigid insulation into which concrete is placed onsite. Both methods of construction yield panels with exterior insulation layers over a concrete core. Wiring may be run through ICP""s by creating electrical chases in the exterior insulation layers. This may be achieved by pre-molding the layers or by cutting or routing chases into the rigid insulation after panel assembly. Regardless of the methods used, electrical receptacles and connections of electrical wires must occur at electrical box locations. Presently these boxes are installed by cutting away the insulation layer where the box is to be located and gluing the box to the exposed layers. Preparing the hole for standard electrical boxes can involve several tools and multiple cutting and scraping operations.
Construction panels comprise structural insulated panels (ICP""s) as well as insulated concrete panels (ICP""s) and other panels or construction components with layered construction materials.
The present invention relates to an electrical junction box with a specialized mounting flange that allows the box to be mounted in a round hole drilled in a construction panel. The body of the electrical box may have the standard dimensions, shape, mounting holes and hardware of typical electrical boxes, however the electrical box of the present invention comprises a mounting flange that is designed to cover and mount to a round hole drilled in a construction panel.
Embodiments of the present invention may be mounted to the exterior layer of a construction panel with screws, nails, adhesive or other conventional fasteners. Some embodiments may also be attached with specialized clips which engage the exterior layer of a SIP thereby locking the box to the SIP.
Some embodiments of the present invention may also have mounting lugs which engage the inner edge of a hole drilled in the exterior layer of a SIP to stabilize the box and prevent rotation of the box in the mounting hole.
The mounting flange of some embodiments of the present invention may have a thickness that is roughly equal to the thickness of the wall covering material that will be applied to the wall in which the box will be mounted. After the box is mounted, the wall covering can be installed right up to the edge of the box forming a flush surface with the mounting flange. Some embodiments of the mounting flange may have a textured surface or be constructed of a compatible material such that they can be finished in the same manner as the wall covering material. For example, and not by way of limitation, the mounting flange may have a textured or drilled surface appropriate for receiving drywall joint compound. When drywall is applied to the wall it is installed flush with the mounting flange so that a typical drywall joint may be formed between the drywall and the mounting flange thereby concealing the mounting flange from view.
Other embodiments of the present invention comprise a thin mounting flange which may be covered by finish materials and concealed thereunder.
Accordingly, it is an object of some embodiments of the present invention to provide an electrical box that can be mounted in a round hole.
It is also an object of some embodiments of the present invention to provide an electrical box that can be mounted without fastening to framing members.
It is another object of some embodiments of the present invention to provide an electrical box that can be mounted in a construction panel prepared solely by drilling a hole.
These and other objects and features of the present invention will become more fully apparent from the following, description and appended claims, or may be learned by the practice of the invention as set forth hereinafter.